Activator for herbicide

ABSTRACT

A herbicidal composition comprising an effective amount of a biocide and an effective amount of a herbicide activator selected from the group consisting of an alkyl phosphate, an alkenyl phosphate, a hydroxyalkyl phosphate, a polyoxyalkylene alkyl ether phosphate, a salt thereof, a polyoxyalkylene alkenyl ether phosphate, a salt thereof, a polyoxyalkylene hydroxyalkyl ether phosphate and a salt thereof.

This is a division of Ser. No. 08/451,187, filed May 26, 1995, which is a division of Ser. No. 08/166,597, filed Dec. 13, 1993, now abandoned which is a continuation of Ser. No. 07/418,903, now abandoned filed Oct. 5, 1989, which is a continuation of Ser. No. 07/139,720, now abandoned filed Dec. 30, 1987, which is a division of Ser. No. 07/042,545, now abandoned filed Apr. 24, 1987, which is a continuation of Ser. No. 06/725,028, now abandoned filed Apr. 19, 1985.

The present invention relates to an activator for biocides.

Biocides such as inseticides, germicides, herbicides and plant growth regulators have been used in the form of an emulsion, wettable powder, flowable product, grains or powder.

The physical properties of the biocides have been modified variously so as to exhibit the activity of the active ingredient sufficiently. However, it has been impossible to further increase the effects of the biocide.

It is quite significant to further increase the effects of known biocides, since the development of new biocides is now very difficult.

After intensive investigations, the inventors have found that specified compounds are effective in further activating various biocides. The present invention has been completed on the basis of this finding.

The invention provides a biocidal composition which comprises an effective amount of a biocide and an effective amount of a biocide activator selected from the group consisting of an alkyl phosphate, an alkenyl phosphate, a hydroxyalkyl phosphate, a polyoxyalkylene alkyl ether phosphate, a salt thereof, a polyoxyalkylene alkenyl ether phosphate, a salt thereof, a polyoxyalkylene hydroxyalkyl ether phosphate and a salt thereof. The invention may be provided in the form of an emulsion concentrate which comprises 10 to 70 weight percent of the biocide and 10 to 50 weight percent of the biocide activator, 3 to 20 weight percent of an emulsifier and 10 to 50 percent weight of an organic solvent, or a dilute composition which comprises 100 to 5,000 ppm of the biocide, 200 to 10,000 ppm, preferably 500 to 5,000 ppm, of the biocide activator and a carrier for dilution. The diluent composition is usually prepared just in advance to use thereof.

The alkyl phosphates, polyoxyalkylene alkyl ether phosphates and salts of them according to the present invention may be prepared by known processes. For example, they are obtained by reacting an alcohol (if necessary, after addition of an alkylene oxide thereto) with phosphorus pentoxide and, if necessary, neutralizing the reaction product.

The starting alcohol has 1 to 22 carbon atoms and contains a straight-chain or branched alkyl group, an alkenyl group having double bond(s) or hydroxyl group(s) in the chain or a hydroxyalkyl group. The alcohol contains preferably 4 to 18 carbon atoms, 0 to 4, preferably 0 to 2 double bonds and 0 to 4, preferably 0 to 2, hydroxyl groups. The alcohols include, for example, butanol, 2-ethylhexanol, lauryl alcohol, stearyl alcohol and oleyl alcohol.

The alkylene oxides to be added to the alcohol to form a polyoxyalkylene chain include ethylene oxide, propylene oxide and butylene oxide. They may be used either alone or in the form of block or random adducts of two or more of them. The mol number of addition is 1 to 100, preferably 1 to 50.

The addition reaction may be carried out by a known process by, for example, introducing an alkylene oxide into an alcohol in the presence of an acid or alkaline catalyst at 50° to 200° C. under 1 to 5 kg/cm². The alcohol or polyoxyalkylene alkyl ether may be phosphated by various processes. For example, 3 mol of the alcohol or polyoxyalkylene alkyl ether is reacted with 1 mol of phosphorus pentoxide at 80° to 100° C. for about 6 h to obtain a corresponding phosphate easily. The obtained alkyl phosphate or polyoxyalkylene alkyl ether phosphate is a mixture of a monoester and a diester in substantially equal amounts. Though excellent effects are exhibited when the activator for biocides of the present invention is any of the monoester and the diester, particularly excellent effects are obtained when it is a monoester, particularly a polyoxyalkylene alkyl ether/phosphoric monoester or a salt thereof.

When said phosphate is neutralized with a base, a corresponding polyoxyalkylene alkyl ether phosphate salt is obtained. This ester salt also has an excellent activating effect. The salts include alkali metal, alkaline earth metal, monoethanolamine, diethanolamine, triethanolamine and ammonium salts.

When the activator for biocides of the present invention is used in combination with a biocide, the effect of the biocides can be increased 2 or 3-folds irrespective of the variety of the biocide.

The activator of the present invention is used in an amount of 0.05 to 20, preferably 1 to 15 parts by weight per part by weight of the biocide.

The biocide may be in the form of any of an emulsion, flowable product, wettable powder and powder. Therefore, other additives such as an emulsifying agent, dispersant and carrier may be incorporated therein according to the form of the biocide.

The activator of the present invention may be used by incorporating the same into the biocide of the above-mentioned form according to the formulation or by applying the same to a subject in combination with the biocide at the time of the application of the biocide in a diluted form. The activating effect according to the invention can be obtained in both cases.

Though the mechanism of such a remarkable activation of the biocide by the activator of the present invention has not been fully elucidated yet, it may be presumed that the activator for biocide of the present invention has an extremely high power of solubilizing the biocide irrespective of the structure of the biocide and, therefore, the biocide is finely divided and the penetration thereof through the surfaces of plants or into insects and germs is accelerated.

The present invention provides also a biocidal process characterized by spraying an emulsion (or dispersion) of a biocide containing the above-described activator.

Examples of the biocides which are activated by the activator of the present invention will be given below, which by no means limit the biocides to be activated according to the present invention. The activator of the present invention can be used safely without damaging the farm products. The insecticides include pyrethroid insecticides such a Fenvalerate [α-cyano-3-phenoxybenzyl-2-(4-chlorophenyl)-3methylvalerate] and Pyrethroid [cyano(4-fluoro-3-phenoxyphenylmethyl-3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropanecarboxylate]; organophosphorus insecticides such as DDVP (2,2-dichlorovinyldimethyl phosphate), Sumithion (dimethyl-4-nitro-m-tolylphosphorothionate), Malathone {S-[1,2-bis(ethoxycarbonyl)ethyl]dimethylphosphorothiol thionate}, Dimethoate [dimethyl-S-(N-methylcarbamoylmethyl)phosphorothios thionate), Elsan {S-[α-(ethoxycarbonyl)benzyl]dimethylphosphorothiol thionate) and Baycid [O,O-dimethyl-O-(3-methyl-4methylmercaptophenyl)thiophosphate]; carbamate), insecticides such as Bassa (O-butylphenyl methylcarbamate), MTMC (m-tolyl methylcarbamate), Meobal (3,4-dimethylphenyl-N-methylcarbamate), NAC (1-naphthyl-N-methylcarbamate); as well as Methomyl {methyl-N[(methylcarbamoyl)oxy]thioacetimide} and Cartap {1,3-bis(carbamolythio)-2-(N,N-dimethylamino)propane hydrochloride].

Examples of acaricides include Smite {2-[2-(p-tert-butylphenoxy)isopropoxy]isopropyl-2-chloroethyl sulfide}, Acricid (2,4-dinitro-6-sec-butylphenyl dimethylacrylate), Chlormit (isopropyl 4,4-dichlorobenzylate), Acar (ethyl 4,4-dichlorobenzylate), Kelthane [1,1-bis(p-chlorophenyl)-2,2,2-trichloroethanol], Citrazon (ethyl O-benzoyl-3-chloro-2,6-dimethoxybenzohydroxymate), Plictran (tricyclohexyltin hydroxide) and Omite [2-(p-tert-butylphenoxy)cyclohexyl-2-propinyl sulfite].

Example of the germicides include organosulfur germicides such as Dithane (zinc ethylenebisdithiocarbamate), maneo (manganese ethylenebisdithiocarbamate), thiuram [bis(dimethylthiocarbamoyl) disulfide ], Benlate [methyl 1-(butylcarbamoyl)-2-benzimidazole carbamate], Difolatan (N-tetrachloroethylthio-4-cyclohexane-1,2-dicarboxyimide), Daconol (tetrachloroisophthalonitrile), Pansoil (5-ethoxy-3-trichloromethyl-1,2,4-thiadiazole), Thiophanate-methyl[1,2-bis(3-methoxycarbonyl-2-thioureido)benzene], Rabcide (4,5,6,7-tetrachlorophthaloid), Kitazin P (O,O-diisopropyl-S-benzyl phosphorothioate), Hinonsan (O-ethyl-S,S-diphenyldithiophosphate) and Propenazol (3-allyloxy-1,2-benzothiazole 1,1-dioxide).

Examples of the herbicides include Stam (3,4-dichloropropionanilide), Saturn [S-(4-chlorobenzyl) N,N-diethylthiolcarbamate), Lasso (2-chloro-2',6'-diethyl-N-(methoxymethyl)acetanilide), Glyphosate [N-(phosphonomethyl)glycine isopropylamine salt], DCMU [3-(3,4-dichlorophenyl)-1,1-dimethylurea) and Gramoxone (1,1'-dimethyl-4,4'-dipyridium dichloride].

Example of the plant growth regulating agents include MH (maleic acid hydrazide) and Ethrel (2-chloroethylphosphonic acid).

[EXAMPLES AND EFFECTS ]

The following example will further illustrate the activators for biocides of the present invention.

EXAMPLE 1

A compound of the present invention was dissolved in a commercially available herbicide (Karmex wettable powder, Simazine wettable powder, Paraquat solution or Glyphosate solution) to obtain a 0.2% solution. 10 ml of the solution was sprayed to each pot of crabgrass (a weed of Gramineae) which had been grown uniformly. The herbicidal effects of them were compared with one another. The crabgrasses used were in a three- or four-foliate period having a height of about 10 cm. Each pot had 25 crabgrasses. The dilution rate of said Karmex wettable powder, Simazine wettable powder, Paraquat solution or Glyphosate solution was 1/300. The herbicidal rate was determined by weighing the above-the-ground parts of the crabgrasses 10 days after the spraying and the results were represented by percentage based on the weight of untreated grasses. The results are shown in Table 1.

                                      TABLE 1                                      __________________________________________________________________________                       Herbicidal rate (%)                                                            Karmex                                                                              Simazine                                                                  wettable                                                                            wettable                                                                            Paraquat                                                                            Glyphosate                                                      powder                                                                              powder                                                                              solution                                                                            solution                                      __________________________________________________________________________     Activator of the present invention                                             POE(3) 2-ethylhexyl phosphate                                                                    84.0 67.2 98.2 100                                           POE(3) POP(5) 2-ethylhexyl                                                                       80.8 68.5 99.1 100                                           phosphate         100                                                          POE(3) POP(5) 2-ethylhexyl                                                                       81.0 68.9 99.0 100                                           phosphate/diethanolamine                                                       POE(10) octyl phosphate                                                                          78.4 70.5 100  100                                           Potassium POE(10) octyl                                                                          79.8 72.4 100  100                                           phosphate                                                                      POE(30) lauryl phosphate                                                                         85.7 80.2 100  100                                           POE(30) lauryl phosphate                                                                         86.0 81.5 100  100                                           monoethanolamine                                                               POE(60) POB(10) palmityl                                                                         78.8 82.4 100  100                                           phosphate                                                                      Sodium POE(60) POB(10) palmityl                                                                  72.1 82.0 100  100                                           phosphate                                                                      POE(25) POP(10) oleyl phosphate                                                                  89.1 89.5 100  100                                           Ammonium POE(25) POP(10) oleyl                                                                   89.5 87.8 100  100                                           phosphate                                                                      POE(80) linoleyl phosphate                                                                       88.4 88.1 100  100                                           Calcium POE(80) linoleyl phosphate                                                               89.4 89.9 100  100                                           2-Ethylhexyl phosphate                                                                           69.0 60.0 95.0 97.2                                          Lauryl phosphate  70.1 72.5 90.4 90.0                                          Oleyl phosphate   75.2 79.0 94.0 92.0                                          No activator used 21.0 18.4 64.2 68.4                                          Comparative                                                                    POE(3) 2-ethylhexyl ether                                                                        51.2 42.8 69.0 70.0                                          POE(10) octyl ether                                                                              49.0 40.4 72.0 78.4                                          POE(30) lauryl ether                                                                             52.5 54.5 72.0 80.5                                          POE(25) POP(10) oleyl ether                                                                      57.5 52.8 79.5 75.5                                          POE(60) POB(10) palmityl ether                                                                   45.4 42.1 72.8 75.6                                          POE(80) linoleyl ether                                                                           60.5 55.2 79.2 80.0                                          __________________________________________________________________________      Note: Symbols POE, POP and POB represent polyoxyethylene, polyoxypropylen      and polyoxybutylene, respectively. The numerals in the parentheses             represent the mol number of addition.                                    

EXAMPLE 2

Third-instar larvae of plant hoppers were cultured and the insecticidal effects of insecticides thereon were examined by the leaf dipping method 3 repetition. Each group consisted of 10 larvae. The insecticidal effects were compared with those in an untreated group 24 h after the treatment. The results are shown in Table 2.

The insecticides used were a Sumithion emulsion and a Malathon emulsion each diluted to a concentration of 1/2000. The concentration of the activator of the present invention was controlled to 0.1% based on the diluted emulsion.

                  TABLE 2                                                          ______________________________________                                                            Insecticidal rate (%)                                                          50%     50%                                                                    Sumithion                                                                              Malathon                                                               emulsion                                                                               emulsion                                            ______________________________________                                         Activator of the present invention                                             POE(3) 2-ethylhexyl phosphate                                                                       84.5      80.5                                            POE(3) POP(5) 2-ethylhexl phosphate                                                                 82.5      78.4                                            POE(3) POP(5) 2-ethylhexyl phosphate                                                                82.5      78.5                                            diethanolamine                                                                 POE(10) octyl phosphate                                                                             80.5      80.0                                            Potassium POE(10) octyl phosphate                                                                   81.2      78.9                                            POE(30) lauryl phosphate                                                                            86.4      82.4                                            POE(30) lauryl phosphate                                                                            86.9      86.7                                            monoethanolamine                                                               POE(60) POB(10) palmityl                                                                            78.5      80.0                                            phosphate                                                                      Sodium POE(60) POB(10)                                                                              82.4      81.5                                            palmityl phosphate                                                             POE(25) POP(20) oleyl phosphate                                                                     90.1      94.6                                            Ammonium POE(25) POP(10)                                                                            86.5      90.0                                            oleyl phosphate                                                                POE(80) linoleyl phosphate                                                                          89.5      92.1                                            Calcium POE(80) linoleyl phosphate                                                                  90.5      92.6                                            2-Ethylhexyl phosphate                                                                              68.2      60.0                                            Lauryl phosphate     75.1      72.0                                            Linoleyl phosphate   85.1      80.0                                            No activator used    49.0      40.0                                            Comparative                                                                    POE(3) 2-ethylhexyl ether                                                                           52.5      41.5                                            POE(10) octyl ether  55.0      40.5                                            POE(30) lauryl ether 55.5      42.8                                            POE(25) POP(10) oleyl ether                                                                         49.0      39.5                                            POE(60) POB(10) palmityl ether                                                                      50.5      40.0                                            POE(80) linoleyl ether                                                                              56.0      45.2                                            ______________________________________                                    

EXAMPLE 3

Male imagines of two-spotted red spider were applied to leaf disks of kidney beans in three replications. Each group consisted of 30 imagines. After the culture at 25° C. for 24 h. 0.2 ml per each group of a test sample was sprayed by the chromatospray method. The insecticidal rate was determined by comparison with the results of an untreated group 24 h after the treatment. The acaricides used were Amitraz emulsion and Osadan wettable powder diluted to a concentration of 1/2000. The concentration of the activator of the present invention was controlled to 0.1% based on the diluted product. The results are shown in Table 3.

                  TABLE 3                                                          ______________________________________                                                            Insecticidal rate (%)                                                            20%       20%                                                                  Amitraz   Osadan                                          Activator of the present invention                                                                  emulsion  emulsion                                        ______________________________________                                         POE(3) 2-ethylhexyl phosphate                                                                       92.5      100                                             POE(3) POP(5) 2-ethylhexyl phosphate                                                                96.0      100                                             POE(3) POP(5) 2-ethylhexyl phosphate                                                                96.0      100                                             diethanolamine                                                                 PIE(10) octyl phosphate                                                                             98.0      95.4                                            Potassium POE(10) octyl phosphate                                                                   98.5      99.0                                            POE(30) lauryl phosphate                                                                            97.5      100                                             POE(30) lauryl phosphate                                                                            90.0      100                                             monoethanolamine                                                               POE(60) POB(10) palmityl phosphate                                                                  95.0      100                                             Sodium POE(60) palmityl phosphate                                                                   92.5      100                                             POE(25) POP(10) oleyl phosphate                                                                     100       100                                             Ammonium POE(25) POP(10) oleyl                                                                      100       100                                             phosphate                                                                      POE(80) linoleyl phosphate                                                                          100       100                                             Calcium POE(80) linoleyl                                                                            100       100                                             phosphate                                                                      No activator used    58.2      64.2                                            ______________________________________                                    

It is apparent form Example 1 to 3 that the activators of the present invention have an excellent activating effect. In addition, each composition as prepared in Examples 1 to 3 was diluted with water. The obtained dilute one was effective to improve the biocide activity. Each component content in the dilute compositions is given below.

    ______________________________________                                         In the compositions of Example 1                                                      activator     2000 ppm                                                         Karmex        1660                                                             Simazine      1660                                                             Paraquat       800                                                             Round-Up       660                                                      In the compositions of Example 2                                                      activator     1000 ppm                                                         Sumithion      250                                                             Malathon       250                                                      In the compositions of Example 3                                                      activator     1000 ppm                                                         Dani-Cut       100                                                             Osadan         225                                                      ______________________________________                                     

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:
 1. An agricultural herbicidal composition which consists essentially of an effective amount of an agricultural chemcial herbicide and an effective amount of a substance for increasing the herbicidal rate of said herbicide; said herbicide being 2-chloro-2',6'-diethyl-N-(methoxymethyl)acetanilide; and said substance being selected from the group consisting of an alkyl phosphate, an alkenyl phosphate, a hydroxyalkyl phosphate, a polyoxyalkylene alkyl ether phosphate, a polyoxyalkylene alkenyl ether phosphate, a polyoxyalkylene hydroxyalkyl ether phosphate and salts thereof, said substance having from 1 to 22 carbon atoms in the alkyl or alkenyl group thereof, the weight ratio of said substance/said herbicide being in the range of 1/1 to 15/1.
 2. A composition as claimed in claim 1, in which said substance has 1 to 100 oxyalkylene units and the alkylene group therein has 2, 3 or 4 carbon atoms.
 3. A herbicidal composition as claimed in claim 1, in which each of said phosphates is a monoester of phosphoric acid.
 4. A herbicidal composition as claimed in claim 1, in which said substance is a polyoxyalkylene alkyl ether phosphate monoester, a salt thereof, a polyoxyalkylene alkenyl ether phosphate monoester, or a salt thereof, said alkyl and alkenyl groups having 4 to 18 carbon atoms and the number of said oxyalkylene units being from 1 to
 50. 5. A herbicidal composition as claimed in claim 1, wherein said alkyl is selected from the group consisting of lauryl and palmityl, and said alkenyl is selected from the group consisting of 2-ethylhexyl and linoleyl.
 6. A method of controlling weeds which comprises applying to a weed growth medium a herbicidally effective amount of a composition as defined in claim
 1. 7. A new composition as claimed in claim 1, in which said substance is anionic and is selected from the group consisting of a polyoxyalkylene alkylether phosphate, a polyoxyalkylene alkenyl ether phosphate, and salts thereof.
 8. A composition as claimed in claim 1, in which said substance is selected from the group consisting of an alkyl phosphate and an alkenyl phosphate.
 9. A composition as claimed in claim 1, in which said substance is selected from the group consisting of a hydroxyalkyl phosphate and polyoxyalkylene hydroxyalkyl ether phosphate.
 10. An agricultural herbicidal composition which consists essentially of an effective amount of an agricultural chemical herbicidal, an effective amount of a substance for increasing the herbicidal rate of said herbicide and an inert carrier; said herbicide being 2-chloro-2',6'-diethyl-N-(methoxymethyl)acetanilide; and said substance being selected from the group consisting of an alkyl phosphate, an alkenyl phosphate, a hydroxyalkyl phosphate, a polyoxyalkylene alkyl ether phosphate, a polyoxyalkylene alkenyl ether phosphate, a polyoxyalkylene hydroxyalkyl ether phosphate and salts thereof, said substance having from 1 to 22 carbon atoms in the alkyl or alkenyl group thereof, the weight ratio of said substance/said herbicide being in the range of 1/1 to 15/1.
 11. A herbicidal composition as claimed in claim 10, in which the herbicide is 2-chloro-2',6'-diethyl-N-(methoxymethyl)acetanilide and the substance is a polyoxyalkylene alkyl ether phosphoric monoester or a salt thereof.
 12. A herbicidal composition as claimed in claim 10, which comprises from 100 to 5,000 ppm, based on the composition, of said herbicide, from 200 to 10,000 ppm, based on the composition, of said substance and the balance is an inert carrier. 